Explanation:
Twice a year, at the Spring and Fall
equinox, the Sun rises due east.
In an emphatic demonstration of this
celestial
alignment, photographer Joe Orman recorded this
inspiring
image of the Sun rising exactly along the east-west oriented
Western Canal, in Tempe,Arizona, USA.
But he waited until March 21st, one day after the northern
Spring equinox in 2001, to photograph the striking view.
Why was the rising Sun due east one day
after the equinox?
At Tempe's latitude
the Sun rises
at an angle, arcing southward
as it climbs above the horizon.
Because the distant mountains hide the true horizon, the Sun shifts
slightly southward by the time it clears the
mountain tops.
Waiting 24 hours allowed the Sun
to rise just north of east and arc back to an exactly eastern alignment
for the photo.
Today's equinox
finds the Sun on the celestial equator
at 0649Universal Time.